Electrically-operated musical instrument.



M. L. SEVERY & G. B. SINCLAIR.

ELECTRICALLY OPERATED MUSICAL INSTRUMENT.

APPLICATION FILED MAYH. 1912.

1 ,1 88,564. Patented J une 27, 1916.

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APPLICATION FILED MAY 11. I912 1 188,564. PatentedIuneZi, 1916. ZSHEETS-SHEET 2- 25 Fig.5

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H UNITED STATES PATENT oEEIoE.

iuEIJvI L. SEVEEY, OE ARLINGTON HEIGHTS, MASSACHUSETTS, AND GEORGE IB.

SINCLAIR, OE GEORGETOWN, MAINE, ASSIGNOLRS To GHORALCELO COMPANY, OF

BOSTON, MASSACHUSETTS.

A GQRPORA TION OF MAINE.

ELECTEICALLY-OPERATED MUSICAL INSTRUMENT.

Specification of Letters Patent.

Patented June 2'7, 1916.

Application filed May 17, 1912. Serial No. 697,923.

To all whom it may concern:

Be it known that we, MELVIN L. SEVERY, of Arlington Heights, in the county of Middlesex and Commonwealth of Massachusetts, and GEORGE B. SINCLAIR, of Georgetown, county of Sagadahoc, in the State of Maine, both citizens of the United States, have invented certain new and useful Improvements in Electrically-Operated Musical Instruments, of which the following is a full and exact description.

This invention relates to that type of mu: sical instruments wherein tuned bars or rods constitute the sonorous bodies; and the invention has for its object the provision of means for electromagnetically vibrating such rods or bars; for electromagnetically controlling their damping; for reinforcing the tones emitted by said rods or bars, and of improved means for supporting the latter.

Referring to the drawings forming part of this specification, Figure 1 is a sectional elevation of the instrument embodying the invention, electrical parts connected therewith being shown in perspective diagram. Fig. 2 is a perspective view of certain rods or bars, showing one method of their suspension. Fig. 3 is a cross section of certain rods or bars. Fig. 4; is an under view of one of the bars, showing its tuning device. Fig. 5 is a sectional elevation of a slightly different form of the invention. Fig.- 6 is a similar view of another form. Fig. 7 is a sectional detail view of the preferred form of the suspension device for the rods or bars. Fig. 8 is a detail elevation of a part of the same.

The tuned rods or bars 1 are usually arranged in two series or rows supported by a single frame, each rod in one row being preferably only a semi-tone in pitch from the corresponding bar of the other row, and both rows or series making up the gamut for which the instrument is designed. These rods or bars usually rest upon supports, as

- shown .in Fig. 6, but we prefer to suspend upon the supportsin the customary manner, the bars are certain to be bodily attracted by such electromagnets into contact with the latter, and no musical notes can be obtained, nothing save a buzz or a metallic rattle. If the electromagnets are positioned below the bars, the felt supports will yield and permit the same objectionable results. The problem is hence a far more diflicult one to solve than in the case of a taut metallic string, whose ends are fixed and which is incapable of further transverse translatory movement besides its sonorous vibrations; since the tuned bar must be supported in such a manner as to leave it perfectly free to vibrate, while at the same time it must not be drawn into contact with the electromagnet whose intermittentattraction is vibrating it.

After much experiment, we discovered that by suspending the bars, instead of supporting them from beneath, and having the suspenslon means incapable of elongation,

we can successfully vibrate the tuned rods or bars electromagnetically.

As shown in Fig. 2, we prefer to provide three points of suspension for each bar, at each such point an eye 2 being attached, to which is secured a small loop or link of gut or silk, as at 3 in Figs. 7 and 8. This loop 3 engages the lower end of a wire 4 which is rotatably held by a threaded thimble 5 turning in a correspondingly threaded hole in the Supporting bar 6. By screwing said thimbles up or down, the bar supported thereby may be adjusted to the exact position relative to electromagnets disposed for the vibration thereof. For the electric actuation of these rods or bars 1, electromagnets 7 are located at proper striking points of each bar, preferably one at each end and 'one at the middle of the bar, with the central one opposite to the other two. To these electromagnets electric pulsations are translivered to a' selected electromagnet 7 by the depression of a key 10 hearing a brush 11 into touch with a contact 12.

The circuit of each electromagnet e1nbraces the current-source 13, wire 14, disks 8, brush 9, wire 23, electromagnet 7, wire 22, electromagnet 7 wire 2l,another electromagnet 7 wire 17, contact 12, brush 11, and a common wire 20 back to said source. It is hence seen that the current to all three electromagnets associated with a single rod or bar is delivered to them simultaneously and in series. This simultaneous action not only causes the rod or bar to be vibrated with triple energy, but provides other advantages which will be hereinafter pointed out.

By arranging the electromagnets as specified, the mid-length of each bar, while being vibrated, will. be drawn upward at the instants the ends are drawn downward, thus not only intensifying the actuation thereof, but insuring that there shall be no tendency to transverse bodily translatory movements of the bars and consequent impact with the electromagnets. In other words, were the electromagnetic pulls at one side alone of each bar, as from below, the constant succession of stresses upon the bar in opposition to the suspending devices would tend to stretch the latter so as to require the electromagnets to be withdrawn farther than desirable from the bar to prevent actual contact with the electromagnetsj but by thus equalizing the action of the magnets upon the bars, there is absolutely no stress upon their suspension means, and consequently no danger of bringing the bars into such obj ectionable contact.

It is apparent that in the case of bars suspended by links 3, the unbalanced upward stresses of the upper central electromagnet alone would immediately attract the bars into contact with such magnet. This balanced method of vibrating the bars is of even greater importance where the bars rest upon felt supports in the usual manner, as

illustrated in Fig. 6, as by our method the bodily movement of a bar toward the electromagnets is prevented without securing the bar in a way which might spoil its tone. This balancing of stresses is further insured by having the central electromagnet' substantially equal in attractive power to both the opposing electromagnets combined. This balancing of electromagnets is indicated in Fig. 1 by showingeach terminal magnet as single, while the central electromagnet is represented as double, although there are other ways of varying the electromagnetic energy of the opposing electromagnets. A further advantage found to result by thus having the electromagnets on one circuit of diflerent resistance or electromagnetic moment, is that the sparking at the brushes 9 is materially reduced-and said brushes and disks 8 made to last considerably longer.

For augmenting the resonance of the bars, resonant chambers 25 are fixed'upon opposite sides of the bars from the electromagnets, each chamber consisting preferably of a tube 25 open toward the bar and closed at its opposite end; said tubes being supported by fixed bars 26, as shown in Figs. 1 and 3. In. Fig. 1 two resonators 25 are represented, one above either end'of the bar. Each end of the bar corresponds to the center of a loop or ventral segment, and each resonator hence stands opposite such a segment, where it is most effective. Not only do these resonators 25 increase the sonorous effect of the vibrating rods 1, but we find that they increase the damping effect of whatever damping devices are employed, and especially of those controlled electromagnetically.

The dampers for the bars or rods 1 are pivotally supported at 29, and are normally held in contact withthe bars or rods by tension springs 30. For withdrawing the dampers from such contact during the actuation of the rods or bars, each damper is provided with an armature 31 positioned in the field of an electromagnet' 32, the energizing current to which is received from the source 13 through a lead 34, and thence through a lead 33, wire 17, contacts 11, and common wire 20 back to said source. The damper magnets are therefore energized by current controlled by the keys 10, but so shunted around the pulsation devices that none of such energizing current is pulsatory.

To prevent the rods or bars from indulging in any swinging or dancing motion, we prefer to use some comparatively soft substance, as felt, between the bars and the rails (3 from which they are suspended. This felt 36 exerts on y a gentle and elastic restraint, leaving the bar free to effect its sonorous vibrations.

For better enabling the rods or bars to be tuned, we solder to the mid-length of each a transversely arranged wire 35, composed of some comparatively soft metal so as to be easily filed down for raising the pitch of the bar bearing it. (See Fig. 4.)

We do not confine ourselves to three electromagnets for the vibration of each rod or bar, sincejtwo alone may be employed, as shown in Fig. 6, or one alone, as in' Fig. 5, but the full number of three appears to be, most satisfactory.

Neither do we confine ourselves to the particular means for vibr ting the bars 1, inasmuch as there are other ways of actuating the same in conjunction with our special means for suspending them, damping them, or augmenting their resonance, or of balancing them under the effects of pluralized means for delivering timed impulses thereto.

differs from such construction or plan in many particulars, notably in that we,employ a freely suspended or supported bar in contradistinction to a stretched Wire or string,

and further in that the electromagnets are located on opposite sides of such bar and simultaneously exert their force in opposite directions on different portions of the bar. So far as We are aware this'involves a new construction and a new principle or mode of operation.

It is further to be noted that under our construction the pulsations of the current are initially timed by means wholly distinct from and independent of the vibrating body, and the pulsations are hence not determined by such vibration but the vibrations are positively controlled by the means which times the pulsations. Hence the rate or frequency of vibration may be varied and determined at will by varying the speed of the mechanism which produces the current pulsations. The expression means for delivering timed electric pulsations, used herein, is therefore to be understood as covering any means which initially determines the rate of pulsation of the current, and therethrough determines the rate of vibration of the sound-producing body.

It is common in the electrical art to mount an oscillating armature on a pivot or axis between the poles of an electromagnet, to curve the magnet poles and the ends of the armature, and to make said curved faces concentric with the axis of oscillation. This is done with a view to maintaining the extremities of the armature and the pole pieces in close proximity during oscillations of the former, and to retaining the armature within the field of attraction of the magnet throughout as great a portion of its movement as practicable, the armature being moved in one direction by a spring or weight, and in the other by magnetic attraction, or by being polarized and alternately attracted and repelled by reversal or polarity of the magnet or the armature. Our invention is not concerned with effecting such oscillations of a pivoted member, and in the embodiments wherein magnets are located upon opposite faces of a bar and at different points in the length thereof, their function and effect is to distort the bar, or effect its vibration by moving difi'erent portions in its length simultaneously in opposite directions.

What we claim as our invention and for which we desire Letters Patent is to wit: a

1. The art of vibrating a rod or bar which consists in subjecting opposite faces thereof to simultaneous oppositely-pulling electromagnetic impulses of a frequency corresponding to the desired frequency of vibraas follows,

tion, the impulses acting upon one face being delivered at a different point in the length of the bar from those acting upon the opposite face. a

2. The art of educing a musical tone from a tuned rod or bar which consists in subjecting opposite faces thereof to simultaneous oppositely-acting electromagnetic impulses of a frequency suited to the tone desired, the impulses at one face being delivered at a different point in the length of the bar or rod from those delivered at the other face.

3. In combination with a rod or bar, electromagnetic means for delivering thereto impulses of a frequency to educe from said rod or bar the tone desired, said means being located on opposite sides of the rod and at different points in the length thereof.

4. In combination with a'tuned rod or bar, electromagnetic means for delivering thereto impulses of a frequency to educ'e from said rod or bar the tone desired, said means being located on opposite sides of the rod or bar and at different points in the length thereof.

5. A musical instrument comprising rods or bars tuned in musical relation; electromagnets located on opposite sides and at different points in the length of each rod or bar; and means for delivering to the electromagnets of the respective bars, pulsations of frequencies to educe therefrom the tones desired.

6. In combination with a tuned rod or bar, a plurality of electromagnets located on opposite sides and within attracting distance of said rod or bar, the several magnets being located at different points in the length of the rod or bar; and means for delivering to the several electromagnets simulbar, supports intermediate its ends; electromagnets disposed upon opposite sides of said rod or bar and facing different ventral segments thereof; and means for delivering electric pulsations to the several magnets simultaneously.

9. In combination with a tuned rod or bar and with supports therefor intermediate its ends, three electromagnets, two located upon one side of the rod or bar and near its ends, and the third located on the opposite side of said rod or bar at the Inidlength thereof; and means for delivering to the several magnets simultaneously, pulsations of a frequency to educe from said rod or bar the tone desired.

10. In combination with a tuned rod or bar and with supports therefor intermediate its ends,three electromagnets, two located upon one side of the rod or bar and near its ends, and the third located on the opposite side of said rod or bar at the midlength thereof, the last-named magnet being equal in strength to the other two combined; and

means for delivering to the several magnets simultaneously, pulsations of a frequency to educe from said rod or bar the tone desired.

11. In combination with a tuned rod or bar, a fixed support above said rod or bar, and suspending means connected at their upper ends to the fixed support and at their lower ends to the rod or bar; an electromagnet located in attractive relation to said rod or bar; and means for delivering to said magnet pulsations of a frequency to educe from said rod or bar the tone desired.

12. In combination with a tuned rod or bar, means for supporting the same freely in space; electromagnets disposed at opposite sides of the rod or bar, at different points in the length thereof, and in alternation with the points of support, the aggregate magnet strength at one side of the bar being equal to that at the other side thereof; and means for delivering to said electromagnets simultaneously, pulsations of a fre- 'quency to educe from said rod or bar the ,tone desired whereby the rod or bar is caused to vibrate about the points of support and the forces acting in opposite directions are balanced, thus neutralizing any tendency toward bodily movement of the rod or bar relatively to its supports.

13. In combination with a tuned rod or bar, an electromagnet positioned within attracting distance thereof; means independent of the vibration of said rod or bar for delivering to said magnet pulsations of a frequency to educe from said rod or bar the tone desired; means for damping said rod or bar; and means operating simultaneously with said bar-actuating means for undamping said bar.

1 14. A musical instrument comprising, in combination, a fixed support, a'tuned rod or bar beneath said support; suspending devices attached at their upper ends to the fixed support and at their lower ends to the rod or bar in the vicinity of the nodal points thereof; a resilient material filling the space between the fixed support and the rod or frequencies to educe therefrom the tones desired.

16. A musical instrument comprlsmg, 1n combinat1on,a tuned rod or bar; electromagnets located on opposite sides of the rod or bar, those on one side alternating with those on the other, and the aggregate strength of those on one side equaling the strength of those on the opposite side; and means for simultaneously delivering to all of said magnets electric pulsations, whereby they are caused simultaneously to attract and move different portions of the rod or bar in opposite directions.

' 17. In combination with a tuned rod or bar and with suitable supports therefor, means for'setting up sonorous vibrations in said rod or bar; and a plurality of resonators alternately located on opposite sides of the rod or bar, each opposite a ventral segment thereof.

18. In combination with a tuned rod or bar, an electromagnet for vibrating the same; a source of current for said magnet; a pulsation-producing device in circuit with saidsource and magnet, for initiating in the magnet circuit pulsations of a frequency to educe from the rod or bar the tone desired; a damper for said rod or bar, normally in damping relation thereto; an electromagnet for withdrawing said damper, included in a branch circuit; and a key-controlled switch for simultaneously closing the main and branch circuits containing said magnets,

19. In combination with a tuned rod or bar and with electromagnetic means for effecting its vibration, suspending means for said rod or bar located at a plurality of points, two of said points being situate near opposite edges of the rod or bar near one end thereof, and the third of said points being situate midway between said edges near the opposite end of said rod or bar, whereby said rod or bar is maintained in proper plane.

20: A musical instrument comprising, in combination, a tuned rod or bar, suspension devices therefor, one located in the medial plane of the rod or bar near one end and the other two located on opposite sides of said medial plane near the opposite end thereof,

frequency to educe therefrom the tone desired.

21. A musical instrument, comprising, in

- combination, a tuned rod or bar; suspension devices for said rod or bar, each comprising an eye fixed in the bar, an adjustable eye suitably supported, and a link joining said eyes; and electromagnetic means for imparting to said rod or bar pulsations of a frequency to educe therefrom the tone desired.

22. A musical instrument comprising, in combination, a tuned rod or bar; an elevated su port for said rod or bar; a plurality of threaded thimbles turning in said support; wires, one loosely passing through each thimble; an eye for each wire, fixed to said bar; a link joining each such wire and its eye; and electromagnetic means for imparting to said rod or bar pulsations of a frequency to educe therefrom the tone desired.

23. A musical instrument comprising, in combination, a tuned rod or bar; an elevated support for said rod or bar; non-metallic links ]01I11I1g said bar and supporting means; yielding material located between said bar and supporting means immediately about said links; and electromagnetic means for imparting to said rod or bar pulsations of a frequency to educe therefrom the tone desired.

In testimony that we claim the foregoing invention, we have hereunto set our hands this'l3th day of Ma 1912.

' MEL IN L. SEVERY.

GEORGE B. SINCLAIR.

Witnesses: V v

CHARLES W. GRocKER, GEORGE I. FISKE. 

